Measles, Rubella, and Mumps in Mexico: A National Serosurvey Highlighting Reemergence Risks

ObjectivesDespite the availability of effective vaccines, achieving the seroprevalence thresholds recommended by the World Health Organization (WHO) for eliminating measles, rubella, and mumps remains a public health challenge. MethodsA retrospective, cross-sectional serological survey was conducted, including 9,587 serum samples collected from 31 of the 32 federal entities of Mexico between September and December 2024. IgG antibody levels against measles, rubella, and mumps were quantified using chemiluminescent immunoassays. Seroprevalence was analyzed by age, sex, and geographic region. ResultsThe overall seroprevalence was 78.3% for measles, 88.6% for rubella, and 81.5% for mumps (p<0.05). Age-stratified analysis revealed significant gaps in immunity against measles and mumps, particularly in the 10-39-year-old group, in which seroprevalence dropped below 70%. In contrast, more consistent protection against rubella was observed across all age groups, although younger children showed lower antibody titers. Regional analysis indicated that only older adults reached the protective threshold against measles in all states. ConclusionsThis study demonstrates that current levels of seroprevalence in Mexico do not correspond to the vaccination coverage recommended by the WHO and highlights the urgent need to strengthen vaccination strategies, conduct catch-up campaigns, and carry out continuous seroepidemiological surveillance to maintain elimination goals.